Rover 416 coolant leak.

OK this one is doing my head in.Apologis for the essay in advance....

Mates 416 P reg injection. Runs like a dream, no lumpiness at idle etc.

However it is loosing a small amount of coolant, and on these engines
that's a doubly bad thing of course. Sat for three hours after a run and
it's dripped enough to make a little patch about three inch across. It's
certainly coolnat it's leaking - there is no air con.

I've swapped the inlet manifold gasket, and that appears to have solved the
leak, for a while. There was another small leak on the bleed screw on the
bottom radiator hose on the cold side of the thermostat - again that's
sorted.

Since the idle is smooth I don't think there is air getting past the inlet
gasket, and it doesn't seem to be ingesting coolant so hopefully there is
no problem there, since that manifold is a pain to get off. The leak now
appears to be dripping down the offside rear of the block around where the
PAS pump is. There is no (visible) leak from the manifold or piping or stat
housing at this point.

I'm tending toward the waterpump now, but I'd like some input as to the
possibilities. IIRC this area is waterpump territory as it sits behind the
stat housing?

Engine has just passed 100k and runs fine. However it's 60k since the
timing belt was swapped (blew a camshaft seal at 40k so new belt). I'm
tending towards a new waterpump fitting as the cambelt is getting towards
replacement - just do both together.

Opinions appreciated..... (also if anyone knows price of waterpump that
would be good too.....)