Moses Leo (concussion), Ativalu Lisati (ankle) and Joe Chan (back) were all unable to finish Saturday's 30-4 loss to Manly, which the Storm entered with a depleted team.
Lisati's injury is the worst of the three and may require surgery following a hip-drop style tackle from Manly playmaker Joey Walsh.
Chan reported back spasms and appears likely to return after the Storm's bye, while Leo could clear concussion protocols in time to also face Gold Coast in round 19.
But star halfback Jahrome Hughes (hamstring) and outside backs Xavier Coates (Achilles tendon), Nick Meaney (calf) and Jack Howarth (quad) are other regular first-graders currently sidelined.
The outside back shortage hurt the Storm against the Sea Eagles, who feasted on the makeshift edges that only became more understrength as the game wore on.
The Storm are also missing forwards Tui Kamikamica and Eli Katoa, both of whom are sidelined indefinitely following serious medical episodes.
"We're just really scraping for outside backs at the moment and obviously losing Tui and Eli for the season as well has probably hurt our forwards a bit," Bellamy said.
Bellamy's reign at the 12th-placed Storm is the longest continuous coaching tenure at any NRL club, spanning 620 games to date.
But the 66-year-old admitted on Saturday night the glamour club was in uncharted waters.
"I wasn't going to complain about that today or last week or whenever, but I don't think I've ever seen the injury toll that we've had this year," he said.
"And some strange injuries, the one to Eli, the one to Tui, they were not run-of-the-mill injuries. Having them out and then also the outside backs we've had injured the last month, six weeks have been quite incredible.
"But it is what it is. Other sides go through it. We just need to learn to navigate that."
The Storm remain eager to draft in talent from outside their squad before NRL clubs must finalise their top-30 rosters on June 30.
Dolphins edge Oryn Keeley appears a contender.
The 23-year-old has already signed with the Storm for next season and has been restricted to only six games at the high-flying Dolphins this year.
The Storm are also expected to sign Bronson Xerri for next season after Canterbury gave the centre permission to test the open market for 2027.
Bulldogs coach Cameron Ciraldo indicated earlier this week, though, that the club had not discussed the prospect of letting Xerri leave mid-season.
"We'd love to get a couple of new players in to bolster our depth," Bellamy said.
"It'd be good if we could get a player or two for the rest of the year. It's been a horror injury run."
