securities account in navision

i m looking for add-on for securities account (shares, bonds, coupons etc) may be, somebody somewhere have created or specialized navision modules for this task. I have some questions about subj. First of all- i will have to develop my module (add-on) or i will base or exisiting module N301 (warehouse, for example). or if add-on for shares exists yet- i wanna buy it. links on demos - good my ICQ is 160531853, e-mail- Thank you.