Here's a solution I've used for months now with no problems. Get a Hoodman 3" loupe, and use gaffer tape to attach it to your K-01. At first, I had rubber bands on it as well... but after a week one broke, and then I realized the gaffer tape was holding perfectly, didn't need any help, doesn't come off when the camera is bumped around. Hollywood magic! Unlike duct tape, it doesn't leave a sticky mess when you take it off. See
ProTapes Pro Gaffer Natural Rubber Premium Matte Camouflage Adhesive Tape, 11 mils Thick, 55 yds Length, 2" Width, Black (Pack of 1): Amazon.com: Industrial & Scientific and also
Amazon.com: Hoodman H-LPP3 HoodLoupe 3.0 Professional 3-Inch Screen Loupe: Camera & Photo ... also, on the end of the loupe, you can turn the diopter ring to adjust it to your eyesight so you never have to take off your glasses (I'm nearsighted).
It has made my K-01 a delight to use. Outdoors in bright sunlight, taking pictures of airplanes against a bright sky, you name it. You see the whole screen with all the information, like the histogram, clear as a bell! As for making the K-01 too large ... well ... once past my RX100 shirt-pocket camera, everything else can be whatever size or weight -- you have to carry it or wear it, so who cares how heavy or large it is.
Using a loupe is much better than struggling to compose with a small DSLR eye-level viewfinder ... no guessing here, you can see clearly what the picture is and you never miss a picture. Fantastic!
Hope this helps -- here's a picture...