Amazon is a good place for that brand, if they don't have it, it's not likely available anywhere.
Good news is that those things are fairly generic, almost any brand in that price range with a similar look is probably the same keyboard.
https://www.amazon.com/dp/B01IUU33UK/ref=sspa_dk_detail_9?psc=1&pd_rd_i=B01IUU33UK&pf_rd_m=ATVPDKIKX0DER&pf_rd_p=f0dedbe2-13c8-4136-a746-4398ed93cf0f&pd_rd_wg=QTlsc&pf_rd_r=WTR8XSFC869CQXHV5AZ9&pf_rd_s=desktop-dp-sims&pf_rd_t=40701&pd_rd_w=veO5q&pf_rd_i=desktop-dp-sims&pd_rd_r=f34b686e-e201-11e8-8f57-65d4f173ec5e...