The ’chain‘ for attaching the fob to the keyring looks identical to the ones fitted to scorpion alarm fobs (the chain is supposed to look like a scorpion tail…vaguely).
A quick Google and this fob looks very similar to other vintage scorpion ones, so if they‘re still in business, it might be worth a call to them to see if they can help. I bought a new ‘chain‘ from them years ago for my Ibiza Cupra R alarm fob and they were quite helpful when I contacted them.