Need Advice: member not sending my parts

Call him out.
I respect the idea of pleasantries, but if this guy has had WEEKS, and is not acting then it is time for you to act. If he was not ready to sell the parts then
the parts should not have been offered in the first place!
It is easy for someone to say "give him time" but it is YOUR MONEY, and the parts should not be offered if he cannot complete the transaction within a reasonable amount of time.
Do not accept the excuses, and let him know it is time.