Good to see vintage parts being refurbished; good luck with that.
Do bear in mind that if you have Barton self-bailers fitted it is most vitally important that you always raise them, absolutely without fail, before beaching the boat. Graunching the bottom on the shore, with these bailers down, risks doing structural damage.
Unlike the hinged types (e.g. Elvstrom/Andersen, and there was also a small plastic hinged one at one time), the Barton ones will not self-close if they hit an obstruction.
(And if I remember correctly, there was also a plastic one of broadly similar design, in probably the sixties, which I would expect would safely snap off in the event of impact, without damaging the hull.)
Oliver