1. The length of time depends on your wife's nationality and what embassy would be processing the application. Doesn't sound like she is Italian as you said she has a tourist visa and Italy is visa exempt. However, if she has been legally admitted to Italy for year (not living there for a year but
allowed into the country for at least a year) she could have the application processed at the embassy in Rome but they may not be as fast as the embassy in her home country. Check out processing times in this link.
http://www.cic.gc.ca/english/information/times/international/05-fc-spouses.aspIf you do decide to travel to Canada, yes, you can sponsor her from here BUT buy a comprehensive health care insurance package as her health care would not be covered by the Canadian system.
2. No, as a PR you cannot sponsor your wife while living outside of Canada. The only thing that is potentially in your favour about working for a Canadian company is that it may count towards maintaining your PR because you are working for a Canadian company. Research the meaning of "Canadian Company" pertaining to immigration law. This is taken from the Immigration and Refugee Regulations:
Division 2
Residency Obligation
Canadian business
61. (1) Subject to subsection (2), for the purposes of subparagraphs 28(2)(a)(iii) and (iv) of the Act and of this section, a Canadian business is
(a) a corporation that is incorporated under the laws of Canada or of a province and that has an ongoing operation in Canada;
(b) an enterprise, other than a corporation described in paragraph (a), that has an ongoing operation in Canada and
(i) that is capable of generating revenue and is carried on in anticipation of profit, and
(ii) in which a majority of voting or ownership interests is held by Canadian citizens, permanent residents, or Canadian businesses as defined in this subsection; or
(c) an organization or enterprise created by the laws of Canada or a province.
Exclusion
(2) For greater certainty, a Canadian business does not include a business that serves primarily to allow a permanent resident to comply with their residency obligation while residing outside Canada.
Employment outside Canada
(3) For the purposes of subparagraphs 28(2)(a)(iii) and (iv) of the Act, the expression "employed on a full-time basis by a Canadian business or in the public service of Canada or of a province" means, in relation to a permanent resident, that the permanent resident is an employee of, or under contract to provide services to, a Canadian business or the public service of Canada or of a province, and is assigned on a full-time basis as a term of the employment or contract to
(a) a position outside Canada;
(b) an affiliated enterprise outside Canada; or
(c) a client of the Canadian business or the public service outside Canada.