But you might find them pretty horrible!!
NatureDiet is available in the UK and Ireland and has a large bag of frozen raw tripe chunks available. Dried tripe is already the creme de la creme of treats for most dogs but the frozen fresh chunks are especially exciting for the dogs. Tripe is a very healthy food and you could even give it as a meal once a week or so. I actually give the chunks to them still frozen and this is especially nice on a hot day.
If you are in Ireland, Dog Training Ireland carries the Nature Diet raw and tinned and pouch foods and treats, and Petmania and some other places do too. You can find them on Facebook for both UK and Ireland and get more info. They will be starting a new cat raw frozen line as well -- I had a few advance samples and the cats love it. It has also been a bit of a miracle food for one of my elderly ill cats who had/has some unknown malady -- I assumed the worst, a hidden tumour; tests come back OK for lots of other things. One possibility was IBD. She had lost a lot of weight and had very poor runny stools for a very long time. She was also very thin and often listless. The options had really come down to trying her on low dose prednisone to settle her stomach and buy her some time...
Then I decided to try an all raw diet. It's been about 3-4 weeks now and she is like a different cat; regaining weight and her stools are back to normal for the first time in 3 years or so. And she is back wanting to play. So now all cats are on Nature Diet prepared raw; the dogs get it alternating with a good prepared cooked diet or homecooked. Oh -- and to my suprrise the cats really like the dogs' prepared tripe diet which also has heart and liver -- a nice mix for cats or dogs!
But the frozen tripe is a very nice doggy treat to keep on hand (if a bit disgusting for humans!! ).