Ok, I am going to be mounting a scope on my Mossberg 500A. I will be using the Weaver No-Gunsmith Converta Shotgun Mount http://www.amazon.com/dp/B00162QKT6/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=2IM1D7FMH353W&coliid=I47T0BTALWWFR Weaver Shotgun "No Gunsmithing Converta Mount Multi slot base allows you to mount a variety of optics including scopes, red dots, lasers while obtaining the optimum eye relief I am looking at a nice Centerfire scope, http://www.amazon.com/dp/B004IKYKOA/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=2IM1D7FMH353W&coliid=I1SLL548EPPWAB but it comes with dovetail rings. I have figured out I need weaver rings. Trying to find some that will hold up to a shotgun without spending a ton. Hopefully under $20. Preferably on Amazon.