wwe transcendent card help needed

[seamantrevor]

hi guys, i'm very new to these cards in general,

i just wondered i want a one touch case for this but theres different thickness someone said these are 180pt cards and i would need 180pt one touch case's is that correct before i buy?

also someone said fold and put a penny sleeve behind the card is there a reason for this?

also is there any websites apart from ebay for buying these cards?
thank you guys any help would be appreciated