Mvala, who has been outstanding this season for the Lions of the North, is believed to have attracted interest from Orlando Pirates among other teams.
Da Gama, however, insists the Golden Boot contender is not for sale locally.
"No, there is no chance of us selling Mothobi Mvala. A team offered us R10m and we refused. I can’t divulge the name of the team. Highlands Park is not a selling team. All these players have two years or more on their contracts," Da Gama told reporters after his side's 2-1 defeat to champions Mamelodi Sundowns at Makhulong Stadium on Tuesday.
"Nobody is going to touch any of these players because we want to achieve something. We can’t keep building for other teams. We did it in the past but now we have to build our team.”
'ODG' continued: "I won’t say Highlands Park is well off after turning down the R10m, but financially we are very sound. The money would have not made a difference.
"Mothobi is a top goal scorer in the league. The eight or 10 points that his goals won us are worth more than R10m to the team. How much is the PSL status?
"His goal return is not disappointing, especially since he missed out on two games against Pirates. If his return is disappointing, then what about Jeremy Brockie? They paid R8m for him. How many has he scored? There are other big and expensive players that are not scoring five goals for their teams.
"The club is actually looking at selling Mvala to an overseas team, not to PSL sides.”
Mvala is joint-second with Cape Town City's Siphelele Mthembu on the PSL scoring charts with seven goals - one goal behind Black Leopards forward Mwape Musonda.