you could buy a mech keyboard for down to 25 bucks check this out:
https://www.amazon.com/ONE-UP-G300-...ical+keyboard&qid=1565123361&s=gateway&sr=8-8
if you genuinely prefer membrane to mechanical then you could go for ornata chrom and remove the plastics from inside the switches (really simple procedure
View: https://www.youtube.com/watch?v=7WN8qrHCZ1g
) in the video he uses tool but i did it with a pencil. anything small that can fit in there really will work but be careful not to damage the keyboard.anyway the ornata has incredible rgb.better than nearly any mech keyboard so take that into consideration.
also razer cynosa but i believe its a bad choice
for half the price you could get the corsair k55 which is also from a very reputable brand and has great rgb and good membrane switches (yes there are good and bad ones)
other than that or if you have a low budget , anything works... go to your local store and get a feel for a bunch of decent looking membrane boards and pick one.