If they took my license for a pending DUI case, is it possible to get a duplicate license or a temporary license until the case is complete?

Normally, your license is not suspended until the conviction is registered. If you did receive a notice of suspension, you can file for a supersedeas from PennDOT's suspension, in the Clerk of Courts. All of the time deadlines to do this are on the Notice of Suspension you received. Take your papers to an attorney.