Is it possible to disable the ability to earn an award weapon on an individual map?

If you mean without editing the sides then i don't think that is possible. Incase you mean with editing them then here is an easy tutorial.
1. Go into the soldier default odf's and delete the award weapons from that.
2. Go into the weapon before that would 'award' the award weapon, for example for a rep rifle go into "rep_weap_inf_rifle" and you will see the class parent "com_weap_inf_rifle"
3. Go into that class parent.
4. Delete the 2 lines: ScoreForMedalsType = # and MedalsTypeToLock = #.
5. Munge and they shouldn't appear when you would get that award normally.