Everton are listed at 4/1, Newcastle 7/1, Crystal Palace 14/1 while Spurs are 16/1 and West Brom 20/1.
However, yesterday news broke that big-spending Wolves could make a shock £20million move for Gray.
With Gray refusing to sign a new contract with just 12 months of his current deal to run, Burnley boss Sean Dyche is prepared to let the striker leave for the highest price.
If Wolves did outbid the Hammers it would mean a hometown return for Gray, who was in the Wolves academy until the age of 13, before joining Shrewsbury Town.
West Ham received £6.5m for Ashley Fletcher and said to be in the market for a back-up striker who would be happy to wait out their time on the bench.