Thanks for the useful suggestions. Here's what happened in the end.
Today I went into "Go Outdoors" a local big camping shop, found two camping tables with plastic tops & steel legs ( folding "X") at £11 each. Then to B&Q to get some conduit clamps & now I have what I need for twenty two quid.
The timber is 1.50" x 2.5' x 6' teak (or Honduras Mahogany - can't be certain with all the crud on it ) and was a science lab bench top in a school built in the 1950's. Tomorrow - weather permitting - I'll belt sand off the old varnish from my bit of wood, finish with an orbital, wire wool & probably Danish Oil. I plan to fit two wooden bars with steel lips, glued & screwed underneath & the inner part of the legs will fit under the lip, the weight of the table top keeping it steady. The conduit clamps will of course be screwed to the outer underside of the wood so they can be folded away.
The legs are quite sturdy, but I have it in mind to cross brace them at the bottom.
Photos in due course, ST collection displayed!
Regards,
Kim Siddorn