SO as far as I know, none of the Marauders-era characters have official official wands (and if they do, no they don't shh) so I put some thought into it and here is what I think what wands people have.
James- Wood: Ebony (Good for dueling and Transfiguration), Core: Unicorn Hair (View later post for why I think this is important), Length: 12 inches, and slightly rigid.
Lily- Wood: Hornbeam (Extremely loyal to their masters; will never take another), Core: Phoenix Feather, Length: 12 inches, and very flexible.
Sirius- Wood: Blackhorn (Performs well for fighters), Core: Dragon Heartstring, Length: 9 & 1/2 inches*, and mildly flexible.
Remus(yes ik he has an official wand shhh)- Wood: Black Walnut (Seeks out mindful masters), Core: Unicorn Hair, Length: 13 & 3/4 inches, and flexible.
Peter- Wood: Larch (Makes owners more self-assured), Core: Dragon Heartstring, Length: 10 & 1/2 inches, and rigid.
Regulus- Wood: Yew (Powerful for dueling), Core: Dragon Heartstring, Length: 9 & 1/3 inches*, and flexible.
Barty Crouch Jr.- Wood: Hazel (Not recommended for temperamental people), Core: Unicorn Hair, Length: 11 inches, and mildly rigid.
Lowkey know that lots of marauders characters don't have official wands but this is all I got for now :\
*I personally hc that the Black Family seemingly always has shorter wands. They will always get chosen by a shorter wand, and if they try to use a longer one, it will always backfire.