Post sight
anybody know if the old made in El Paso scopes will stand up to the recoil of a 458 on a fairly light gun?

I had one on a ruger 77 458wm for about 10 years. It held up, however the optics are not as clear as they are now --25 years later. Eye relief about 2.75 inches

The fixed power older Weavers are tough and often recommended for high horsepower rigs. K3's and K2.5's are good scopes that are hard to break, have fair resolving and bright optics but lack waterproofing. I have found eye relief to be around 4", great to have on the big pushers.

The old K fixed power scopes had a reputation for being tough as a boot. Eye relief should be adequate. The optics didn't provide the resolution that most scopes now offer, but I doubt that you're shooting ground squirrels at 400 yards with this rig, so clearly seeing your target is hardly an issue. So long as you are not in simultaneously cold and humid conditions, their lack of watertightness and propensity to fog internally isn't much of an issue, either.