I would just buy the melamine stones sold by Yellow Mountain Imports, either the single convex or the double convex. Or you can buy these glass stones for US$20 on Amazon.com https://www.amazon.com/Quantum-Abacus-Basic-Go-Mod-CL-701/dp/B08314WRQQ/ref=mp_s_a_1_fkmr0_2?keywords=porcelain+weiqi+stones&qid=1585715657&sr=8-2-fkmr There is this set for about US$40. https://www.amazon.com/Elloapic-Exquisite-Ceramics-Stones-Yellow/dp/B084Z1Z9SH/ref=mp_s_a_1_46_sspa?keywords=weiqi+stones&qid=1585715864&sr=8-46-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFVMkEyTERYWVZSME0mZW5jcnlwdGVkSWQ9QTAxMjYwNzMzQVNWVzEwQUZXU0tWJmVuY3J5cHRlZEFkSWQ9QTA4NTk2MDkzSENFRDI3UlJCRExHJndpZGdldE5hbWU9c3BfcGhvbmVfc2VhcmNoX2J0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU= This set for under US$25 has just stones and bowls. https://www.amazon.com/Melamine-Single-Convex-Stones-Jujube/dp/B018V2O4LE/ref=mp_s_a_1_17?keywords=baduk+stones&qid=1585716066&sr=8-17 When searching, type in "weiqi stones" or "baduk stones" and you should get plenty of relevant results.

Then, if you have some experience making things, you can get a workable board by following the instructions on the following webpage. https://www.bamsoftware.com/go/board.html