is it a cota 200 or mh200 ?

[billp]

help required to identify my new purchase to hopefully obtain proof of manufacture date to enable registration for road use for dvla, bike was bought as a cota 200 but having doubts now as may be a mh200, it came with a white tank and cota 200 decals but has a montesa honda vin plate rivitted on front of steering stock and also a stamped number on side of steering stock both numbers are the same and start as MH200 prefix,  the engine number has the same last three digits as the frame number but starts with 29H so numbers appear to be matching, however the 29H is puzzling as sources suggest 29M should be the prefix, the frame has the engine protection loops and the carb is the amal mk2, have tried contacting honda uk when i thought the bike was a cota 200 but they were unable to date bike saying numbers incomplete ?  hoping someone can help or suggest who to contact to identify bike.