Thru hulls and ball valves

When we replaced our valves after almost 10 years use some were like new on the inside whilst others that looked OK on the outside but were badly corroded on the inside. The engine sea water intake and the sullage tank drain valves were in the worst condition. One of the sullage tank valves was leaking because the "ball" part of the valve was scored. The nipples in each case were corroded and very thin. The air cond sea water inlet valve was also in poor condition. Our engine sea water inlet valve is 1 1/4" with a 90 degree 38mm nipple. The sullage tanks drain valves are 1 1/4" with 38 mm nipple with a 90 degrees nipple. The air cond sea water thru hull is 1". I think it is better to replace all the valves rather than leave a few which could fail in a few years time. 

Instead, I have decided that the simpler thing to do was import BSP valves, a few BSP thru-hull fittings in case we wreck some getting the old bronze ball valves off, and BSP thread-to-barb adapters from a country where that's the standard.  I randomly selected the UK and found that I could live with the ex-VAT pricing given how much I'll save by not swapping out 20 perfectly fine thru-hulls.

I'll circle back in a month or so with either lessons learned or a successful report.  Thank you to those who provided feedback on this thread topic -- it prevented a major derailing of the project.