Other support from the Commonwealth?
Well, hands up who's ever heard of the Uganda War Fund? Which paid for (amongst other things) aircraft during the Battle of Britain?
No, I hadn't until recently, either.
Here's a contemporary (1940) account from an Australian newspaper (I've come across African periodicals mentioning it as well, but Australian material is more accessible online).
Kalgoorlie Miner (WA : 1895 - 1954), Friday 25 October 1940, page 5
nla.gov.au/nla.news-article95200213
Money for Aeroplanes
UGANDA'S CONTRIBUTION
London, Oct. 23. — The central committee of the Uganda war fund has remitted £12,000 to Crown agents for payment to the Minister of Aircraft Production for fighter 'planes. This sum, together with previous amounts of £42,000 and £6000, brings the total to £60,000. These amounts represent one fighter plus £10,000 towards the completion of a Uganda squadron.
The Uganda Government suggests that the first Uganda fighter flight be christened with the names An-kole, Buganda, Busoga, Entibee, Jin[...] Kampala, Ruwenzori, Teso and Mbale.