I think the Bentley did not belonged to this group of racing cars. Somewhen i've got a little brochure about 30 years MoY (12 pages).
On page 6 is announced the release of the 4 racing cars in june of 1986 as the first 4 exemplar. Sadly this serie wasn't continued.
On page 5 is already the Bentley. This car was released in 1985. One year before they began the "Grand Prix Racing Cars".
Very interesting are three other facts. The pictures of the Maserati and the Ferrari are confused. All cars haven't racing numbers. And the color scheme of the E.R.A. is different with the later sold cars. The chassis frame is here also blue as the rest of the chassis.
"Matchbox Toys" by Dana Johnson say that the E.R.A. made in China are rarer as the same made in England.