1A is going to make the LM317 mighty warm and maybe even
put you onto overtemp limit unless you spend some effort on
the thermal management and maybe supplement with an external
pass transistor (see copious application figures).
A switcher ought to cost not much more (you can buy cheap
ones now at near cost parity, especially if you factor in the
finned aluminum and fan).
Now, "charger" has come to mean more than some amps at
fixed voltage. Charge control is a thing. Do you need some?
In that case, more complex ICs might want a look.