I'd refer to MP4024 as an "single inline pinout (SIP) integrated circuit (ic)" with four high current darlington pairs. Toshiba call it a "TOSHIBA Power Transistor Module Silicon NPN Epitaxial Type" if that helps.

I can never buy parts in stores here in Canada. I have to order them online from Mouser, Digikey, Newark, etc. and shipping/minimum order is a killer. Generally not cost effective to try and fix small electronics unless I can save up and do a larger order of parts.

Hope you get things working.
D.