We are a musical group from Nashville, TN. We have been invited to Ireland to play a festival for needy children who are interested in studying the arts, but lack funds for proper guidance, instruments, supplies, et al.
We would really love to help, however we lack the funds to get there.[YOUTUBE] Theo Cas.

You pay for it from the profit you have saved by performing.
You pay for it from your own pocket. You can try and raise money by letting your fan base know and ask them to send money to help with the trip.