Learn me some...sewing machines?

https://www.amazon.com/LORJE-Sewing-Machine-Class-Bobbins/dp/B008MM5BDE/ref=asc_df_B008MM5BDE/?tag=hyprod-20&linkCode=df0&hvadid=196304134456&hvpos=&hvnetw=g&hvrand=9878810966726784406&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9007652&hvtargid=pla-315195515991&psc=1

Metal bobbins, also here is where you can get new bobbin holders 

https://www.amazon.com/Sewing-Machine-Bobbin-Loading-Machines/dp/B06ZY7SBBV/ref=pd_bxgy_img_2/138-2152820-3895838?_encoding=UTF8&pd_rd_i=B06ZY7SBBV&pd_rd_r=03e35ef1-6e78-4ebc-955e-90f9e5e7eea0&pd_rd_w=6oNLl&pd_rd_wg=qFAln&pf_rd_p=bd257e40-8799-42ac-88d0-f76e0faf3886&pf_rd_r=CERAFZ568EWT12DHWQ0S&psc=1&refRID=CERAFZ568EWT12DHWQ0S

Double check that they work for your machine, but its worth trying to replace those. 

In reply to Apexcarver :

Unfortunately those are not the right type of bobbins for the 700 series(can't find any metal bobbins for a 700 series), the "touch and sew" models use a bobbion that winds in place. Since I have shelved that machine until I can get it serviced, I picked up a new Singer "Heavy Duty" 4400 series...it uses the bobbins you listed above that are NOT wound in place. Now I seem to be making some progress: 

I did try the double needle to get a double stitch working, but ended up bending the double needle when it ran over a 3 layer section on a test piece...so evidently I am limited to 2 layers, at least using a general purpose foot. The double stitching does work, I just need to be careful, since I only have one more double needle at the moment.

Old thread revived by spammer.  Move along, nothing new to see here.