Repair windows 1984 tilt aluminum single hung double pane manufacturer unknown builder grade

A handy person from Fort Worth, TX says:
I have about 16 windows overall, but my priority is to get 6 fixed in the front - they get lots of west sun, don't work at all. I am reasonably handy and just removed one sash to take photos. I believe the original springs are all stripping internally or in the sash blocks, and none help to balance the weight. My spring tubes are 3/8". The sash is 42" wide by 30" high and quite heavy. Got it back into the frame and didn't weigh it however..... The springs show wear at the color tip and no color (greasy black). The tubes show splitting at the lower end seam so I think they may be under- weight for the window weight. Our biggest complaint is the weight we have to lift just to open!

Can you suggest these parts for ONE window So I can try to update one as a test. This would help me determine if the full job needs doing on all my windows. We are 50/50 on the cusp of whether or not to fully repair the existing 16 windows or just commit to full replacement of all windows. Some of the windows are tough to get open or sticking badly or stuck shut, etc. So doing one window will tell me!

Parts I would need for one window (or as you suggest):
- 2 tube springs of 3/8" Diameter (ends are 2 pins set 1/2" center to center, entire spring unit is 29" overall minus 1 " for end protrusion minimum. Spring shaft material is 3/16" wide by 1/16"+ thick - seems the split casings I am seeing suggest these were too weak for this heavy window sash???

- 2 slide blocks - see photos of details - missed but I believe the thickness is 3/8", and other dimensions are 1&7/8" long by 15/16" wide. Note photo detail of sash lock pin hole in block and photo of the pin itself with matching underside slot. Not sure if yours can match up???

- 2 sash lock pins - if I need new pin design to match your slide lock design.

- Sash Bottom seal - approx. 7/16" depressed width of existing seal and 38" long (40" sash width but 2" short in the existing installation - shouldn't it be 40" long to completely seals the sash bottom on the frame?

- 4 'fur' seals each 30" long (or 120" total seal material if sold by yard, etc.
(two are for outer facing of sash sides to frame, two are for inner sash side track to inside frame)

I would probably buy some spares if I go for the full 16 window job - I few of the lock pins are bent or broken, for example.

Just got frustrated with trying to attach my 7 photos - your system stops at five and would not upload them - kept failing. If you are interested please email me and I will reply with them as an attachment.
A handy person from Fort Worth, TX says:
Here are my photos!
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Profile picture of Casey
Casey from SWISCO responded:

Perfect. Your photos appear to be showing our S900-28 spiral balance, 15-145 pivot shoe and 26-041 pivot bar. You can view our selection of weatherstripping here. Feel free to send side profile images of your seals and dimensions if you're having trouble matching up the correct replacements. Thank you!

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