Ok, Yes you have a B type axle. 1967 is good because you can use all the pontiac GTO tempest lemans parts and also 65-67 olds 8.2 10 bolt parts too.
The after market makes posi units and gears for your housing too.
NOW if you have a limited slip diff (positraction) (your calling it a spool and probably should call it the 'carrier unit' posi or open and the rear end housing would be the whole 'rear axle assembly'. then we have 'axle shafts '
SPOOL: to most guys is for drag racing and will permanently lock both axle shafts togehter never having any slip or unlock effect in corners...strickly and drag race item.
MINI SPOOL : are 4 blocks in most rears that lock the rear as a spool does but cheaper and there is no need to change a carrier unit or in ford 9" case it is a single little round spool that goes into a carrier unit.
Finally you have ID ed the rear correctly...BUT you really need to make certain you have a LSD unit (limited slip diff unit ) in the housing assembly, the only way to truely know is to open the rear cover. then you will be able to find out the ratio from the outer diameter edge of the ring gear and if you post pics we can tell you if it is a LSD unit or open standard carrier (single wheel peel)
If you do need not help please ask or visit
www.jdrace.com i am there too. Just GM diff info and help.
If you want your original posi unit reconditioned we can do that or ask for pricing on a new unit too. Hope this all helps. Jim
I added a picture of what the unit will look like...Obviously not as clean this is what yours would look like when recondtioned.