I find it hard to let them go always if a lot of work has gone in to them. Minnie was a nightmare and in truth if I had known how many problems it had I would probably have just broken her up for parts. She had a lot of work plus a pro camera tech cost of £50 to calibrate her afterwards.
Geno and Sven (XG-M and X-500) have probably had about 20 hours work each to bring them to pitch perfect, Sven has a small mark on the focus screen but as I am selling this one on I wont replace the screen. The screens near perfect just with a small ring at the extreme top edge. They bot needed a fair amount of elbow grease to get the finish to come up to snuff, internal and external cleaning, new capacitors for the XG-M, lenses both utterly filthy with oil apertures and solid grease in the focus, aperture readouts snacked, battery compartments corroded etc etc etc. Because I have OCD nothing is ever left to 'good enough' and I tend to obsess easily and only when its as perfect as it can be made do I tend to sit back.
After all that - yes its hard to let them go and I sometimes wonder if the new owner will ever respect the tool and the work that I have had to do to make it like new.
Cost for an SRT - it would depend on its cosmetic condition. The black ones can brass in an attractive way or a horrid way. It would depend on a number of things like is there a lens included. Whats the shipping cost. - sometimes on eBay people ask for ridiculous shipping (some of that is down to the GPS program). SRTs vary enormously and even I get confused by the naming and numbering so had to look up the MC.
The SRT MC was a kind of budget version of an SRT 1010 manufactured for exclusive sale through K Mart. Would I pay anything for it ? Nope because I would want a thoroughbred not a slugged version - YMMV.
Big question would be what is it overall condition - generally I find if they are cosmetically good they are generally ok. tests on an SRT would be -
Does the meter run accurately - non functioning can be something simple but it may indicate the light cells are dud - and that happens with these.
Does the speed indicator in the VF work reliably - if not the camera may have had some serious use (the cord that drives these gets slack and the numbers dont register well)
Does the match needle indicator work - thats the big circle looking thing in the VF. If it doesn't some of the internal pulleys and springs may be out of whack and its a painful job to work with these.
Battery chamber clean ?
Prism clean and free from fungus ?
Mirror clean and not showing any de-silvering
Focus screen ok and new clean ?. If not the focus screens are easy to manage - you can whip prism out of an SRT in about 60 minutes of careful work and blow out any crud.
Light seals and mirror bumper are a doddle on the SRT to replace, you can snooze through it
Oh winder lever - watch out as lots of them have broken plastic grips and a spare is likely to end up costing around £10 if you can find one.
IF your one wa clean, looked good and seller seemed honest and you really anted it I would suggest $50 would be a good price - to give you some scale here;
I paid £25 for Minnie complete with a Minolta 50mm f1.7 MC,Vivitar 135MC lens, 35mm MD lens, Minolta Electroflash 20, some filters, complete set of Minolta extension tubes. Camera was in a complete mess but the target was the 35mm MD lens and the 50mm f1.7. Minnie ran ok but her slow speeds was off by a mile and her light meter was non running plus she was full of crud and decayed foam.
Sophie was acquired for £77 and is a complete minter with a minty 58mm f1.4 and case, none off it looked like it had ever been used at all and the seller told me it was bought as a wedding gift and they had never used it. I would believe it. Light seals and bumper were perished but other than that she is sparkling.
Last year paid around £45 for an SRT101 with a Minolta PG 58mm f1.4 which was mint. The target was the lens. Follow dup by a Minolta SRT101 which was near mint which I bagged off for £25 no lens as far as I can recall. The two bodies were refurbed by me and handed to my sons for xmas presents complete 1.7 lens each, owners manual, pack of film etc as a special present from me.
I also bagged a non runner for £4.99 as I needed some parts - it could have been returned to working condition with some (a lot) of effort but I needed some trim parts for another one so it was stripped for spares.
Hopefully that gives some clue as to value - if the camera was clean(wish) and winds on and fires I would consider $50 a good price.