Help wiht the FX Verminator

Hello everyone, my sister want to send me a FX Verminator in .177 because my country don´t allow larger calibers, these are my doubts...in max power setting the verminator can kill a giant rat of 14 pounds at 30 yards at least wiht a head shoot? (see Jutia conga in google) i want to buy a hawke frontier scope for the verminator...Do you guys think it's worth it? the 2 scopes that came in the case are enough? can the verminator be filled with hand pump? in low power what is the shoot count in .177? sorry guys i´ve never seen a pcp in my life...only springers. Thanks in advance..