There are some very well priced lillys on aquarium Gardens website that would suit a small tank, there are also plenty on ebay and lots of cheaper ones from China, just a bit of a risk imo if they are no good. I recently bought a set for just over £30, granted not the best you can buy but they seem OK. Especially for your first ones, just in case you break them.
Call me tight if you want 😉 but even £30 looks bit step at the moment for me found something for lot less that might work, £8.99 this might be worth a risk, the advantage of having the acrylic tube you can bed it to the shape you want
https://www.ebay.co.uk/itm/13mm-17m...rentrq:768261b51720acc737ae4d91fff3b2c0|iid:1