It's a
Lipsey's Special of the Ruger MK512GCL, Mark III version shown here:
I had one just like it, very accurate, nice balance, I paid $349 in May of 2005.
I have an old track on the pistol:
Ruger MK512GCL Pistol in .22 Long Rifle. Bluebook of Gun Values (30th Edition) indicates between $261 in 98% condition and $311 in 100% condition for this gun. I have 9 recorded prices for this model gun from $195 to $375 over a period of 2 Yrs 4 Mos ending October 2, 2007. The average price as of that date was $303. No refurbs, no refinishes, regular sights, adjusted to two magazines (if magazine fed), all represented as 95% or better, no distinction for import location or engineering revision, if any, no special editions, no distinctions for box, papers, tools. Current or last MSRP is $381.
Here's the way the data charts out but I'd be reluctant to claim the average price trend projection is accurately represented. I'd take a guess at within $30 of $350, either way, with magazines, papers and box.