Imperforate Anus and Anal Sex [26m]

I was born with an imperforate anus; it was corrected after birth and I don't have bowel issues as long as I eat right. However I am extremely tight, no more than one and a half, maybe two fingers can penetrate me at a time. This makes a for a nightmare in the bedroom as I wish to be the receiving partner in anal sex. My question - Is there anything I can do to make this more comfortable? Is there some type of surgery I can have that would make the anal opening larger? It currently does not stretch, I can play with it for hours, but the opening is not going to get bigger. So, I feel elective surgery may be the only option if I really want this, but I don't know where to start. On top of it, relationships usually don't grow or last due to I'm always attractted to guys that consider themselves tops. Additionally I really don't have a desire to top them, so that's kinda out - my equipment works just fine and I can, but I don't want to.

This just sucks.

Hopefully I didn't violate any of the subreddit rules - I looked over the FAQ and checked old posts but didn't find anything very useful.

Thanks in advance for any advice or direction. I know I probably should just ask my doctor, but I wanted to try researching on my own first and see what I could find.