Hi,
If you want to add item in the current toolbar, you need to use a custom plugin or an override of the HikaMarket toolbar (view: toolbar / default).
Please note that the toolbar view is used almost everywhere in the front-end so you'll need to perform some context checks to add you elements just in the targeted page.
If you want to add a second toolbar in the view, you just need to put it at the beginning of "productmarket / form".
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.