I had / still have the same problem as you...my bifocal line giving me two 'illusions' in the scope. Last year I had my contacts...single vision...and all was GREAT, until I had to fill out the license tag. Trying to wing my way thru it....I thought about my glasses in my bag. I used the bifocal part to finish the tag. Really weird looking thru 2 prescriptions though.
Contacts kept me with constant eye irration, so they're out. This year, my opt. prescribed bifocals that are placed lower in the lense. Havent been to shoot yet, but if it's the same, I'll have a single vision pair made @ Wallyworld, then put a cheap set of reading glasses in the bag for the tags, etc.
Maybe this will give you some ideas.
(to name a few): DPMS Sportical w/Magpul, Marlin 336 (30-30) and XL7(25-06), Savage 110 (308), Winchester Mod 70 (243), H&R Handi Rifle (7mm 08), Blackhawk .357, Super Single Six 22/22WMR, SR9, SR1911, S&W M&P 45, Ruger LC9. Wishlist includes a SR 40, Mini-14. Dream Pistol - 5 1/2" Redhawk 44 mag. Dream Rifle - M-1 Garand.
***What is GUN CONTROL??? Gun control is hitting what you AIM AT!!! Damn Right I believe in Gun Control!***