Hi Capt...
Not being a tax accountant, I have very few FACTS to offer. BUT, an IRA is not an option for with no "earned" income...bux derived from a J O B....in the States... dividends, inheritances, etc., don't pass muster. Ya didn't "earn" it...it just came diddly-bopping by.
Since the bux you may earn in DR is not taxable, until ya get to some high amount, I seriously doubt you could contribute to an IRA. It (your DR bux) was not taxed in the first place...an IRA is used to defer taxes 'till you're 70 and a half. You can't defer what ya never paid....
Jump on IRS website on the net and you'll get the straight skinny if you're willing to pour thru boatloads of stuff.
Better still, get ya a good tax accountant in the US...your situation is not that complicated....
If he/she wants more than $500 bux for the info, not for total return work, tell him to bark at the moon...
Ol' Phil