I am not a rockabilly guitarist so ignore everything I have to say
With that said, here's my thoughts: First off... your blue junior is a hot little amp. It should do fine for you. Add a little reverb, and you are already at some of the classic sounds.
When I think rockabilly, I think Brian Setzer. Much of the tone he gets come from his hands, but with that said, I am thinking a big Gretch with a Bigsby tremolo would have the right look. Unfortunately I don't know enough about Gretchs to have specific info. I am not sure how much difference there is between a 6120 and the 5000 series. I suspect if you bought a pair of TV Jones classic pickups, that would be a pretty hot setup (or in my case, I'd just need the neck pickup). If I were in your shoes, I think I'd just google what brian is playing and then check my bank account.
On the flip side, there's the chicken picking leaning side of rockabilly (I am not sure if that is on your radar as much)... I am thinking like Bill Kirchen in the video below. I love his classic sound. If you wanted to go for that sound, a tele is the way to go.
It's two different sounds, and I think you can't go wrong either way.
BTW, I've got a T-60. I am the original owner. My parents bought it for me when I was about in 8th grade. It has a tone I like and it plays great. It weighs approximately the same as a boat anchor. That's a big chunk of ash. I did a setup on it and took it up to the church a few months back. It was fun to get it out again.