Championship skins

I only got into league just last year due to a friend and enjoy it deeply. Now i have seen that there are certain skins that are unattainable such as championship riven or thresh and personally i think they're pretty kickass and would love to get them. Reason i came here is to see if I can convince Riot to make the skins sellable again for those who weren't even around for league at such a young stage in development. Please the community of league of legends and riot, make skins attainable again for those such as myself who only recently joined the riff . Thank you for taking your time to read this and I hope that I can reach through with my message and there are some skins you would like to see brought back them put them down and raise some awareness.