Yes indeed. You will be able to wring the very best out the 500 with that 2x410 stack without over taxing your woofers. Rest assured that they will be screaming bloody murder at the top of their collective lungs should you so desire.
Sorry, and how can you pair them if all are 8 ohms, there are no 4 ohms 410 extension cabs...
The full price of the Rumble 100 is $400 before any discount that we enjoy here in the USA, and also take for granted. I don't know what your import tax/duty structure is in Lima, Peru. Plus additional shipping, maybe $470 isn't as big a rip off as you think. Ask for a discount. You just might get it, especially if you are paying in cash.
It's not like you can hop in your Jeep and drive to California in an afternoon and pick up a new Rumble.