Hi Jeff,
I usually make my own by cutting an 1/8" by 7/16" groove in 5/8 to 3/4" material.
Here are a couple of options:
I just found this one online. Have not used it.
http://www.lowes.com/pd_104805-81-87981_4294774692__?productId=3200767&Ns=p_product_ avg_rating|1&pl=1¤tURL=%3FNs%3Dp_product_avg _rating%7C1&facetInfo=
I have used this on steel door frames with great success:
http://www.pemko.com/index.cfm?event=products.productListing&searchName =Search+by+Pemko+Product+Number&openFilter=loadPem koPartNumberSearch&partNumber=306dqd&partCategoryI ds=306DQD%3A899
Not sure that I understood your search exactly.
Did any of these ideas help?
RC/DG
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