This should be easy enough --- Puerto Rico (along with Guam, Virgin Islands, etc) is covered under NMLS so you'd just need to find someone licensed to do business in Puerto Rico.  I don't personally know anyone that has that license, however.

Shane Milne has a profile on AR and is at a Fed Charter, so he may be a good resource if you google him-  I refer business to Shane in areas I am not licensed.

I don't know about those areas but we have a couple of banks here that have Canadian affiliations and I have heard from some of my clients that they were able to obtain home loans from them to purchase property in Arizona.  I want to check back on this question as it would indeed be nice to know of any lenders that are able to do international loans.

Borrower from Chile needs to document funds for down 30% translated into english and 620 pesos to the dollar. What type of income do they have? They need to have income that can be verified for past two years. What type of identification do they have? They will be notarized by an American notary so they need US ITIN and driver's license and passport. The ID may be the most difficult.  Got a source 

Several years ago I worked with a loan officer (who is no longer in the business) at FEMBi Mortgage in Miami. I recall him mentioning they had a brance in Puerto Rico.

I'm sure a google search will provide some leads.

Parked and Curious. 

I certainly hope someone chimes in here with a resource for you.

Interesting situation. Parked

John Meussner has you covered on this question.

An interesting challenge. Good luck.

Interesting situation - curious to find out.