according one of the guys at my shop, with solomon boots especially, the only real difference between an even size and a half size is the amount of padding in the liner. for ex. a size 28 boot and 27.5 boot are the same except the 27.5 have more padding. from trying boots on im pretty convinced too.
if you have an even size you could try to find a half size liner if you could find one.
seems like a dumb idea now that i think about it but w/e ill throw it out there