No, you can't.  You either have Community or Enterprise. But you might want to look at the Odoo Community Association (OCA) Accounting apps for Community Edition.   

https://www.odoo.com/apps/modules/category/Accounting/browse?author=Odoo+Community+Association+%28OCA%29

Not in the same Odoo instance. 

You could implement 2 separate Odoo instances (1 with CE and another with EE) and build an interface between them. But, this would beat the purpose of having an integrated ERP system.