There are some great sites out there that do old regimental ties, I find it difficult depite my regiment only going last year to get some pre 1992 pattern ties in silk (thinner stripes due to changes when Bns dropped from 3 to 2 and some things were updated). I'll google and see if the one that helped me is still there!
These people helped me out but trust me Google is your friend.
I did happen across a current regtl web shop through the MOD site which had Manchester Ties for sale, could have been the Kings/QLRs or whatever they are called nowadays. Web Page Name Web Page Name