that looks like an aussie 250 2v head, and as i recall is uses the standard holley two barrel mounting pattern, which means a holley 2300 or autolite 2100 should bolt right in place of what you have now, since it is a holley 2300. you can get the carb from most any ford V8 with a two barrel carb, i suggest something like a C-code 289, or a 302 powered mustang ll or maverick.
but rebuilding the carb you have is quite easy.