A 4.5 year search - found - Unisonic 766 - a beauty

[d b]

Yep. Different everything. I should get my readers on before I post.
Your's is reminiscent of a Magiclick (made in Argentina) that I bought off ebay with a bad photo. I saw the Enter key but couldn't make out much else and got all excited. No loss. It went to a calculator-loving and as they say on ebaby "smoke free home".
IIRC: it had the same switching and functions as yours so possibly the same ROM, but a different body/case. there were four Argentine and one Brazillian company that I know of who would buy the ROMs and displays but make most everything else on their own. The keys on the Microcifra 10 feel like an HP-91/92/97! They used the Novus Mathematician ROM so the overall accuracy is less than stellar, but usable.