Also have a short chimney 8inch diameter aprox 18 ich long in stainless steel free My IT is also free if anyone is interested its adjustable so will do most sizes mainly stainless steel too.
For sale £25.00 for the below 2 boxes of fibrefrax ceramic insulation 25mm and 50 mm thick these are offcuts a few bits are used to but its a bargain (more than enough to do a big oven) plus a large stainless steel door (cut to size and screw to thermalite blocks to complete)
The boxes of insulation are very large the 2 together are approximatly the sixe of an automatic washer. may cut the door to size if you have a template, will add door max size later
Door width 21 inch and 13 inch high to top of arch made from stainless steel (will need to be screwed to thermalite block or other insulation material as its only thin and will warp otherwise
please pm me for more details sorry unable to post so will be pickup only from castleford west yorkshire or often in Bradford so could arrange something
Edit Got a huge roll of chicken wire too take what you want.