What about department store tool packs, like Home Depot's EGO, remember they have an excellent return policy and you can buy online and return it to the store if something goes wrong.
EGO 56V 7.5Ah Battery C$617.00
EGO 56V 5.0 Ah Battery C$298.00 <----better value then 7.5Ah!
I dont know if they use Sony 25R 18650's. But there is a thread here on E.S. about them.
DEWALT 20V/60V MAX FLEXVOLT Lithium-Ion 9.0 Ah Battery (2 Pack) $329.00
Search list from $High to $Low
https://www.homedepot.ca/en/home/catego ... price-desc
And remember - All those list prices do go on sale!
$980 56V and 26Ah = 1500Wh - viewtopic.php?f=14&t=94752&p=1387763&hilit=ego#p1387891
An EGO pack build - viewtopic.php?f=3&t=83525&hilit=EGO
More EGO - viewtopic.php?f=14&t=93563&p=1369510&hilit=ego#p1369060
An Article - https://www.electricbike.com/cordless-t ... for-ebike/