Hope the experienced and bright minds here might add their views on the suitability of this unit, a 600 watt, 25 amp switcher adjustable from 21.6 to 27.6 volts for command and liaison set use. 

1) Do you think 25 amps will be enough to power both a DM-33 and single DM-32 simultaneously as part of a complete SCR-274-N? (actually the transmitter portion is SCR and the receiver portion and modulator are ARA ATA)

2) How about starting a PE-73 dynamotor to power a BC-375?

3) Could the 25 amp unit simultaneously power a BC-375 and BC-348 as part of a complete SCR-287? 

4) Would it have a hope of powering both an SCR-287 and an SCR-274-N at the same time?

In addition to the PP-1104-C units, which I wish were available in the UK, are there other ready built PSUs worth considering? 

The 25 amp models are available. Unfortunately, the next size up which is 1000 watts, 42 amps adjustable from 20.4 to 28.8 volts is on back order for a year. 

Thank you for your views and help. Photographs of these two projects are here, here, here and here. 

Merry Christmas and Happy New Year,
Adam

*link from above: https://uk.farnell.com/tdk-lambda/rws-600b-24/ac-dc-conv-1-o-p-24v-25a-600w/dp/2444011?st=600%20watt

**25 amp data sheet: https://www.farnell.com/datasheets/2883301.pdf

***42 amp data sheet: https://www.farnell.com/datasheets/3651152.pdf