oh no!, that 0-2mA; 0-30V power supply kit again!

[Jwillis]

I got a transformer  custom made...

Where did you get this done and how much did it set you back?

This is back in 2022, so prices may be different now.
https://www.antekinc.com
Complete order was for two transformers.
AS-3435 - 300VA 35V Transformer  Custom made 0-15-23-35V was $52.00 USD 
Also got a AN-10440 - 1000VA 40V Transformer Custom made 0-10-20-30-40V for $119.00 USD

[Electro Fan]

A couple threads from a similar project:

https://www.eevblog.com/forum/beginners/looking-for-power-supply-kit-to-be-assembled/msg3338264/#msg3338264

https://www.eevblog.com/forum/beginners/question-on-power-supply-diodes/

In the end the completed power supply seemed to operate reasonably well (at least for the price), and the project was fun and a good learning experience.

[Kleinstein]

The nice point if the kit is that it gets away with a simple transformer. Though the choice of voltage is a bit tricky as one usually is rather close to (or above)  the maximum voltage of the OP-amps. The more universal circuit is using 2 separate windings or transformers. Tap switching adds more voltages and the more commone center taped winding is not ideal, though it would probably be the best choice for a kit that does not come with the transformer.

The other kit looks good and may resemble one of the simple lab supplies. Here simpler 2 tap swiching may have been the better choice.