I believe Modelhaus has a repop of the original AMT annual '70 non-RS bumper and grille. And it should be usable--I have an original glue bomb I'm rebuilding; a while back I checked its bumper against the new AMT '70 and found that it should work with only minor fitting here and there.
There's a weapon
That we must use
In our defense
Silence reveals
When you look at them
Look right through them
That's when they'll disappear
That's when we'll be feared
It doesn't matter what they say
In the jealous games people play
I took a kit steel axle to the LHS and bought several LONG pieces of K&S steel wire/rod in the closest two sizes. One or the other works with any wheel. This stuff is tough and requires either a hacksaw or (much faster) cutoff wheel in a Dremel to cut.
The other thing you can do is raid the axles out of another kit in your stash, which I've also done many, many times.
Saw a "toy & train show" on my way to buy the Sunday paper, stopped in. Few if any models this time but a guy with lots of Hot Wheels had a '79 and a '91 Corvette promo, near-mint conditions with boxes, for only $5 each. They're both mine now.
Another great movie tune:
And you my love, won't you take my hand?
We'll go back in time to that mystic land
Where the dew drops cry and the cats meow
I will take you there, I will show you how