No, send the Valentines. You’ve got a Pacific coast nation building them in 1941.
They are not ready in time - production was only just ramping up at CPR Angus Shops in Montreal - Between May and Sept 1941 they had only made 30 tanks - mainly due to unskilled workers 'hand making' the tanks rather than using power tools etc
Production did rapidly ramp up with the 100th tank rolling off the lines in November - but from what I have read about tank quality at this stage of the war that did not necessarily mean that it was ready for war
Indeed many tanks arrived in North Africa with parts missing and were finished in theatre!
And then the tanks have to get to where they are needed ideally with blokes who know how to use and maintain them - 30 tanks by Sept is not enough.
Unless CPR Angus shops gets their act together earlier (POD1?) then unfortunately to all intents and purposes they are not getting to Malaya in anything like meaningful numbers
Another idea is for New South Wales Government Railways (NSWGR) to begin building Valentines at the same time as CPR Angus Shops (POD2) rather than buggering about trying to build a heavy tank (Sentinel)
A better POD (POD3?) is all of the above but that HMG accepts the Valentine design earlier (rumour has it that it was offered as early as FEB 10 1938!) as a war Emergency design to supplement the Matilda II (of which only 2 had been built by the start of WW2 and only 23 were ready by May 1940) and to initially allow replacement of the Matilda I (which while heavily armoured for its time was only armed with a Vickers MMG and was as 'slow as molasses' with an eye watering 8 mph top speed)
That way given the numbers built the Commonwealth might very well find itself with lots of Valentines (and far fewer Covenanters) far earlier than OTL
But without an improvement in production numbers - there are lots of Covenanters sitting around in the Uk being used to train armoured divisions.
As I said - send 300 to help the Aussies build their Armoured Division (300 is good enough to initially equip the 6 'Regiments' (battalions) of the Divisions 2 Armoured Brigades)
By mid/late 1942 they were getting M3 Stuarts and M3 Lees - so by the time the Covenanters would be worn out (6+ months) and in need of serious workshop TLC they start to replace them with US Tanks - but of course with increasing tensions the 1st armor brigade and support group forms up in Malaya and slots in with 8th Division - the rest is used to reinforce Rabaul, Ambon, and Timor with at least a Reinforced company of tanks each.