Any one know about these?Son in Law needs a weaver side mount for this 81,and the chart at Weaver doesn't tell me much,or else I'm over looking some thing.He wants to mount a 3-9x32 or maybe a 3-9x36,one inch tube.It's the same size as a Weaver K4.The chart says #48402 for the base,but I can't tell by the chart what kind of rings he needs.How 'bout it?