where might I find heads for this unit? Thanks!
First welcome to the forum! Welcome
A little work is going to be required to restore this drum to its original configuration (calfskin heads with gut snares). But if you're just looking to get this into a playable condition quickly without regard to originality, clean and lubricate all moving parts, go to your local drum shop and get a Remo Fiberskyn batter head and a clear or hazy snare/reso head (a knowledgeable sales person will know what you need), and reattach those modern steel snares. Again, this would not be the proper original setup for this snare drum, and it would not have its true vintage sound, but it would be playable.
If you're ambitious enough to attempt a full restoration on this drum, there's lots of experts here who will guide you through each step. Very friendly and helpful members here.
Mike