Lens mount help
 

I was given a 28mm RL close focus Vivitar lens, and can't seem to find any info that would help me find an appropriate EOS adapter for the T2i. I can't upload a photo right now but on the lens barrel there is an F/X printed by the mount. Inside the rear lens cap there is an embossed A/FX. Does this mean anything to anybody?

Thanks.

EDIT: here's a link to mount photos.. http://madeupmusic.com/28mm_Vivitar/index.html