There is no online stock, but a few stores show some availability.
The price dropped from $59 to $29 just today so tags might not be updated yet, but will scan at clearance price. Regular price is $119.98. Amazon listing to compare (lowest ever was $74.99)
You can check Walmart availability here:
*Walmart sets status automatically to OOS when stock count drops to 3 or less. The actual availability is YMMV.

Philips E-Series HX7022/64 Standard Sonic Toothbrush Heads can also be found on clearance for $9 (reg. $37.97):

Oral-B Genius 8000 Electric Rechargeable Toothbrush Powered by Braun dropped to $90 in-stores, was $140 previously (reg. $280), there is a thread about this deal when price was $140

Also, related:
Equate™ Kids Clean+ Battery Operated Toothbrush Kit $1 (reg. $11.97):
Colgate 360 Optic White Battery Toothbrush, Soft $1 (reg. $9.27):
Oral-B Kid’s Battery Power Toothbrush Featuring Disney Princess Characters $1 (reg. $7.96):

As always, don’t use stocktrack as an argument when talking with Walmart CSR, use it as your own reference only. The price it shows is the price it will scan in store, actual availability may vary, depending on location.
Good luck!