There are PC to hot shoe adapters out there, and they do work well. However like Steve says, these also introduce another layer to teeter the flash on. I have one (Hama?) that locks in pretty well, and is better than nothing. Getting a flash bracket is a good idea... though the Pentax part is a standard one, it slides into the grooves on both sides of the viewfinder, and sits on top of the prism. The fit is pretty solid... but unless you have a flash that can use a PC cord, you'll need one of those adapters also.
The adpter will be something like this:
http://www.bhphotovideo.com/c/product/89982-REG/Hama_HA_6952_Hot_Shoe_Adapter_2.html
You slide the bottom into the cold shoe, the flash into the adapter, and plug the wire into the PC terminal on the camera.
The most basic type of flash bracket looks like this: you screw the bottom bar into the tripod socket, and put the flash on the handle. This gets the flash out to the side, which can be a good thing. More elaborate ones can be had also. I've used these since the 70s, with cameras lacking a flash mount.
http://www.adorama.com/FABL.html
This is what the Spotmatic flash shoe looks like:
http://www.marketworks.com/StoreFrontProfiles/DeluxeSFItemDetail.aspx?sid=1&...548&i=12698990