With out seeing your hives here is a suggestion.
1.Order a queen.
2. From hive A take a frame of honey, a frame of pollen and 3 frames of brood. (This is assuming that your hive has 8 + brood frames)
3. From hive b take 1 pollen frame and one brood frame and a honey frame (this honey frame could be taken later say next week or as needed.
4. Put all this together in your new hive body, add the queen and move it all to your new site.
NB the brood from hive A should be of varying ages, that is eggs, uncapped and capped. Mix it up so that there will be an even amount of new population coming through.The frame of brood from hive b should be sealed, brush the bees off it and place in the new hive, this is just so you don t have bees from both hives fighting, but it doesn't really matter as they will sort it out as you drive to your new location.
The new caged queen can go into hive A or your new hive, either way. Hive B will be a donor hive for a while, that is if hive A or hive C need more of anything whether it be honey, pollen, brood or bees etc.
Replace good worker comb frames into hive B, into position 3 and 6 or 7 in the brood box, this will encourage the queen to lay and replace as soon as possible.
Hive A will need more brood manipulation than that to push all the brood back together.
Once you order your queen expand you r brood nest as much as possible, that is give you queens plenty of space on good combs to lay.
Anyway read all that and send back any questions and then I'll add some more information.
Good luck.