I do make lined ones Ozzy, but I line them as I go.
Think about where it actually scratches you…..the usual places are the neckline, around the face with the hood, cuffs and forearms.
If those are the only itchy places, then find something (I'm presuming that you've used wool for the shirt and would prefer wool or linen as a lining) suitable and cut matching pieces from the pattern. Just slip stitch those inside the shirt where it itches.
If you have a look at your shirt, guestimate a rough amount of fabric, and a colour range, then I'll have a rake through the remnant boxes and see if there's something there that might do.
I know I have linen, but wool flannel is either in a big enough piece to be used to line an entire shirt, or kind of smallish pieces now since my last clear out.
If nothing I've suggested suits, away to the local charity shop and buy a fine wool pullover and cut that up to line the scratchy pieces. It shouldn't cost much I wouldn't think.
M