In all honesty, there isn't really a replacement for the fetch lands, Standard is much slower, and much harsher on tri-colour+ decks now. Your best bet is the likes of
Evolving Wilds and
Warped Landscape, switching to basics over duals and being more selective on your choice when fetching. You could also run
Traverse the Ulvenwald and/or
Sylvan Scrying as a way of mana-fixing.
For
Wingmate Roc, either try
Hanweir Militia Captain/
Westvale Cult Leader if you, as you seem to be, aim to
flood, and want a beater, or
Pious Evangel if you really want the lifegain effect, also netting you a
Zulaport Cutthroat like effect in your colours.
I think the deck can definitely still work in standard, and I really like the build, but you'll obviously need to adapt your plays a bit for the changes!