Hi Paul,
Most led's should do the trick with emersed set ups, I've got an IKEA £10 jansjo lamp that does well with this kind of thing, however it's not bright to look at.
The other lights I tend to go for are the cheap ones from China on eBay, however given the current situation that's a no-no.
The third one id mention is the aquael leddy, I think it's about £30, but it's a great little clip on light both for aquascapes and emersed.
P.s just seen your note about being free standing...you could use a free standing lamp and change the bulb to something suitable for plants