If it were me, I'd take a stand-alone sublingual B12 and a separate multivit with real folate instead of folic acid. There are a few brands out there with real folate, Thorne is one that's sold lots of places and is quite affordable--they have various B complex, several formulations of multivits (Basic Nutrients is what they call them), quite a few choices really.
If you really think you need extra B12, the mega drops at
www.holisticheal.com are the cheapest I've seen per dose (I just wrote the first part because the bottle is about $35-ish but since it's 1 drop per 1,000 mcg, it's a whole lot of doses, more than 300 per bottle). They have them in as methyl, hydroxy, and adenosyl forms, the hydroxycobalamin is one of the most tolerated.