balance front prop

Hi guys. When im driving along at a certain amount of throttle or when its under strain i get this big vibration. It feels like its comming right from where the front prop is. All joints are fine and had a new UJ on the front prop a few months ago which gave me no probs at all. Thid vibration only started after i rolled my landy, but no steering, suspension, chassis or anything bent. Tracking is bang on as well.
Im thinking i may have bent the front prop slightly when i rolled it? Had a big knock of the front left wheel. Any ideas?
Was thinking that i shoulkd drop off the front prop, stick the diff lock in and go for a drive. no vibration = front prop the problem. Am i right in thinking that?
If that is the case can anyone reccomend where i can get my prop balanced? or should i buy new?
Thanks, Chris

for 70 quid id buy a new one if you discover thats the cause of the vibrations i had those issues on my disco found it was a massssssive chunk of the uj missing not good