You can make some balsa dust and pack it in the holes. Once the holes are full and packed, hit it with some CA. Then go back to the GP horns.

If you can't find hardware locally try www.microfasteners.com
great hardware at great prices, regular and stainless. I usually get stainless but that's just me. Some sample stock numbers to look at would be:
MSPPS0216
MSPPS0224
SCA0216
SCA0220
SCA0224
MSPPS3020
MSPPS3025
SCM3020
SCM3025
http://www.microfasteners.com/catalo...cts/TNMBOX.cfm