I cannot speak very well on who you SHOULD send it to, but I CAN speak from personal experience on who NOT to send it to.
Don't make the mistake I did and send it to Brethern Arms. I would not ever recommend anything go to Brethern Arms.
I sent a C93 to them for a refinish and they were just terrible to deal with. Customer service was crap, crappy job, no attention to detail.
It was a straight forward job - refinish the rifle in a particular black color they offered, and remove the original flash hider and replace with a suppressor mount I provided and included. I sent it all off. I got the gun back and it was the wrong color, the suppressor mount was not added, and they didn't even bother to send it back. I then had to go around with them, then send the rifle back, then they took their sweet time getting the mistake corrected and the job done right. I felt that they were quite flippant in their responses to the problems THEY created. I gave them a chance because they were kind of a start up, the new kid on the block, and their price was better than anyone else's it appeared. And they utterly blew it. I will never do business with them again and will never even look at their website again. I understand mistakes happen and I am a patient guy, but they had me at the stops.
I should have gone with Jeff at PCS or Jason at IGF. Good luck with it!