Hopefully, someone else will reply with specs for this speaker. If not, you might have to break out the signal generator and the calculator and measure the driver yourself. Instructions and examples of the process are shown in the post called "T/S Measurements."

If you are careful, you can measure the values and get within about 20% accuracy tolerance. I think that companies using Klippel measurements probably get more accurate results than this, but it's close enough to build good sounding cabinets. I assume quite a bit of shift in operating parameters, so having perfect T/S values might be of limited value. Some tolerance is expected.

http://www.greatplainsaudio.com/PartsList.html

I'm thinking that you'll have to measure them yourself.

You could try posting here, too:

http://www.hostboard.com/cgi-bin/ultimatebb.cgi?ubb=forum&f=3729

Good luck.

Will keep searching as I have no measuring devices.

http://www.lansingheritage.org/images/altec/catalogs/1971-home/page22.jpg

http://www.lansingheritage.org/images/altec/catalogs/1971-home/page23.jpg

http://www.lansingheritage.org/images/altec/reference/1975-drivers/page07.jpg

Also you might contact this guy for dimensions, maybe even strike up a deal on parts:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3079188936