But the boss says Krovinovic is the priority with Bilic believing he will miss out on goalkeeper Gribc to Atlético Madrid while he feels the Baggies are likely to be priced out of a move for winger Orsic.
In a two-hour video interview in his native Croatia, Albion's head coach discussed his interest in signing his three countrymen as his team gets ready for life in the Premier League.
The Express & Star confirmed last week goalkeeper Gribc is a target.
But there are widespread reports that the 24-year-old is on the brink of joining Diego Simeone's Madrid - something Bilic confirms.
In the interview, Albion's head coach also states he was interested in signing Orsic back in January.
But he said a deal wasn't possible then and he doesn't feel one will be possible this window due to how much Dinamo Zagreb will want for the winger.
The boss also confirmed Krovinovic is a top priority for him this summer.
While he also revealed he expected to have more money available to him, but his budget will be boosted when out of favour players are sold.
"We don't have that much money yet," Bilic told Index HR.
"I expected we would have more.
"I told the owners that we had done a hard job, but also that we had to do something now.
"Krovinovic is a priority, I will do everything for him to stay.
"He has improved a lot, he can play in several positions and whether he is the holder of the game or sitting on the bench he is always smiling.
"Oršić was up to date in January, it was not realised.
"Now it will be difficult to realise.
"I watched Ivo Grbić in Šibenik, he is a top goalkeeper, I try everything if this does not happen with Atletico, but I am not confident."