Here is one in the UK.
Accessories - Instrument Senders & Adapters | Speedy Cables
https://www.speedycables.com/accessories-senders/
I was looking to replace my Smiths mechanical H2o gauge and found one at Merlin Motorsports in the UK for £96.10 and £17.95 shipping ($124 total) It was here in 5 days and saved over $60. Point is be open to extending your searches and purchases.