Definitely order yourself a new screw from a Honda dealer, either online or local. $3 Part #90191-KYJ-900
And while a lot of folks have $200 impact wrenches these days, I am not one of them.
This is what I use to remove stubborn screws:
$13 from this guy: Yamaha XS650 Impact Screwdriver with bit set - Mikes XS - New OEM & Vintage Parts Supply Warehouse
It's a really nice kit and has just the right size bit to fit these screws.
I just put on a set of Oxfords myself, today.
I had to have my nephew come over yesterday to help with the bar-ends.
I heated up the screw head because I really thought I was going to find Lock-tite in there. I didn't. But the 2nd one didn't budge until we heated it, too.
Anyway, I put on a pair of gloves and held the bar-end in place while Mitch smacked the hell out of the impact screwdriver with a 5 pound sledge.
As mentioned - the key to not stripping Phillips head screws is having the correct size bit.
Before things get too bad, you can always get an impact screwdriver (w/correct bit) and put some valve grinding paste on the tip on the bit. That helps to grip the head a little better.