Paul glad to hear you had a "merry" Christmas. Mine was great but busy got two little ones so my house looks like toys r us...seriously it could be!
Ok...most are the same but what you want to find is a smart charger, think I would check at pep boys or advanced auto parts just make sure it is a trickle charger or battery tender not just a battery charger and you should be fine. Now if you want the L emblem for Lexus on your battery charger you may not get it but??? Like I said I have a Harley Davidson..."smart" charger can be used on the car, bike, grass cutter, ME! I wish!
Good Luck...we are supposed to get 6-12 inches of snow Sun and Mon...going to have some fun in the GX!