Holosun here as well!I am a die hard Holosun fan. I have a 510c, several 507Cs and many 407Ks. All are fantastic.
They do offer the RMR with A 3.25 dot that might be an option that could work for you.I have an RMR, 508T and 507K X2.
I hate the RMR. I have an astigmatism and it flares out bad for me. The others have a much finer dot and I can see them without any issues.
thats the one I have.They do offer the RMR with A 3.25 dot that might be an option that could work for you.