Congrats!
Post pictures!
Along with Winners Circle, you can contact Hap Waldrop (he's often here at BCF). His site is:
https://www.acmespeedshop.com
Also, if you want to see some neat parts (but expensive shipping), try Peter May:
https://www.petermayengineering.com/specialistProducts.htm
Another Brit company is Frontline:
https://www.mgcars.org.uk/frontline/
Also, Minimania USA:
https://www.minimania.com/Search_Inventory.cfm
Speedwell:
https://www.speedwellengineering.com/
Huffaker:
https://www.huffakerengineering.com/products.htm
Even if you don't buy from some of these places, it's fun to see look at their webpages and see what's out there.
In terms of clubs, along with the VSCDA, here are some others:
https://www.svra.com/
https://www.hsrrace.com/
https://www.vintagedrive.com
If you want to come a little more north, VRG is an excellent group to run with:
https://www.vrgonline.org/
The VSCCA is also good, but they have a 1959 cutoff and they limit the number of '59 cars. I have heard that there is sort of a waiting list for newer ('55 thru '59) cars to join their events, but I can't swear to that.
It's also fun to look at the European FISC series:
https://www.fisc-racing.com/index2.html
For non-vintage club racing, try the SCCA
Most of here would say the same thing in terms of old race cars.
CHECK THE BASICS!
Look at all brake hoses, pull/inspect all the wheel bearings, look for looseness in suspesion parts, flush all fluids, check valve adjustment, inspect for loose nuts and bolts
everywhere, etc, etc.
Don't worry about any improvements until you are sure all the existing bits are properly screwed together and operating well.
G'luck!