Hi,
You can export the tables and rename them in the SQL file.
You can copy the "jos" tables and export them.
You can import the tables in the new database and then rename them.
You have several possibilies to achieve it ; but yes, it is important that the imported tables have the same prefix that the rest of your joomla 3 tables.
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.