I've always thought the Model 88s (and Ruger's Model 96s) were pretty cool.Very nice! I bought one years ago to go with my M100 & M100 Carbine in .308. Very nice .22 for a full sized person, having the feel of a full sized rifle. The 490 and M100 have since moved on, but the M100 Carbine remains with it's cousin, the M88.
I had heard that once before, and went on a search. From what I recall, yours should be a model 6C (American). The Model 490 wasn't available as a Sears model here in Canada. Up here, 6C (Canadian) got you a Cooey/Winchester (now Savage) model 64/64B. What you have there is probably a pretty rare piece...I think that I have the "Ted Williams" version of that rifle as sold by Sears. Unfortunately, to make it at a little more 'attractive price' they put a plastic sleeve around the barrel and mounted the rear sight on it. Needless to say, plastic is NOT forever and the sleeve cracked leaving the sight floating around on the barrel, useless. No doubt there are ways to fix it (replacements of the plastic do not seem to exist) but it was my best friend's gun (he bought it new, 50 years ago) and I am not sure that I want to change it.