Unlikely to find this sort of chemical in a local store. You'll most likely need to do a bit of driving or order from a company.
I recommend Cytex / Conap's
Conathane (UC30) as the best and you can find distributors closest to you here:
http://www.conap.com/distrib_search.htm (the site itself doesn't mention UC30)
I noticed you're in Reading, PA, USA so your closest distributors are:
Rudolph Brothers & Company
Full Line Distributor
Pittsburgh, PA
USA Scott Merlack
Ph: 724-444-3157
Fax: 724-444-3157
http://www.rudolphbros.com
Smith Group, Inc.
Full Line Distributor
816 Nina Way
Warminster, PA 18974
USA Alex Bonfiglio
Ph: 215-957-7800
Fax: 215-957-9600
http://www.thesmithgroup.com abonfiglio@thesmithgroup.com
E.I.S., Inc.
Full Line Distributor
2825 Southampton Road
Philadelphia, PA 19154-1206
USA Scott Callahan
Ph: 800-367-1212
Fax: 215-673-7320
http://www.eis-inc.com scallahan@eis-inc.com
Smith Group, Inc.
Full Line Distributor
816 Nina Way
Warminster, PA 18974
USA Kent Kramer
Ph: 215-957-7800
Fax: 215-957-9600
http://www.thesmithgroup.com kskramer@thesmithgroup.com