I have not been able to find replacement stock at a reasonable price for the exact model of EasyCap that works with the Portsdown transmitter. Specifically, this is the Fushicai UTV007 with device ID: '1b71:3002 Fushicai USBTV007 Video Grabber [EasyCAP]'.
Having bought 500 in the past 3 years from our Chinese supplier, they are now demanding a minimum order quantity of 1000, which is not practical for the BATC.
I have some other models that are easier to obtain and hope to modify the Portsdown software to use them. When I have done this, I can make arrangements for them to be available again in the BATC Shop.