Wid, I have a very similar pistol to the one in you photo. Mine is a Mark I. Bought it from a co-worker about fifteen years ago for $175. Not sure if it was a good deal at the time. Came with the original grips and a very nice set of wood grips with some good checkering on the bottom half. The left grip has a rest for the thumb. Also came with two clips and a few hundred rounds of ammo in a leather case. Shot it a bit when I got it and found it very accurate and easy to shoot. I think it's time to break it out again for some fun and inexpensive plinking. Thanks for the post to remind me to take it out of the gun case.
From what I have seen in the store and on line a used Rugar MK anything is worth more than you paid. IMO you got a pretty good deal, I would have bought it for that much, no doubt.
Heck yeah, get that pistol out and get to shooting it. They are a great deal of fun and cheap to shoot.