The (L0) attribute of the club you bought is simply referring to the minimum Level you need to be to purchase it.
Fun fact: There is no L0. All players start at level 1 ;)
Serious fact: Clubs that are available early, at low levels, are expensive, since the buyer avoids the grind (and cost) of levelling up.
Same for "slow meter" clubs & balls: They come at top prices!