Benelli 250cc OHC approx 1934 for restoration

1934 approx 250cc Benelli OHC for restoration. The bike is seized in the engine and will not turn over, there is a valve, guide and springs missing from the inlet side of the head.
There is a spare head with a new set of valves. The chain is off the bike and the gearbox and clutch are all complete and kick over. There is an import document from HM Customs and excise dated 5/9/1990 showing duty was paid when the bike came to the UK.
The bike is sold as seen and for restoration also and collection from the UK Lake District area. I would take a Bradshaw sports oil cooled engine, racing JAP JORZ parts, Blachburne 1926 ohv engine or TT Raleigh 1931 racing parts  in part exchange.
I have had the bike for 5 years or more and the only thing I have done is take the chain case off to see if the motor would turn with a spanner on the crank.

A great overhead camshaft project