Oversized pcb stock?

hello everyone, I'm trying, and failing to find a reasonably priced source of double sided pcb stock, either photoresist or plain. I need to make a pcb that's 13" long and can only find 12" stuff or 14" stuff for 3 times the price. Anyone know of a cheaper source or if it's ok to glue a 1" strip to the edge to extend it? Thanks for any input.

Board Type *Maximum Standard Dimensions (inches)
Single-Sided / Double-Sided 16.60" X 22.60"

If you can get away with the old single sided phenolic type stuff, I've got a box of it here !

Original ad here : https://www.electro-tech-online.com/threads/for-sale-uk-large-sheets-130mm-x-380mm-pcb-blank.128173/

On eBay, there is a seller named "abcfab" who sells a wide variety of PCB stock. He'll probably have just what you're looking for or he may even be willing to cut it to your specifications.

I forgot I had this thread open, I musn't come here enough, I've since been in contact with a board house who can make the boards for cheaper than I can, so i'm letting them do the hard work.

The only catch is, I now need to find someone who's willing to buy the spare unpopulated boards... I'm sure I can tempt a couple of friends into 1 or 2 or 6...