The Robins came back from a goal down to claim their second point of the season against Brentford.
However, with just three options at centre-half, Wilson knows he would be desperately short of cover should anyone get injured. The former Hartlepool boss admits he would prefer to bring in someone on a temporary deal, but he has been informed that his targets will not be available on loan.
Wilson told the Swindon Advertiser: "We never thought we were the finished article and we knew we had to strengthen certain areas - that is no different now.
"We've got a long season ahead of us and will not get through it with three centre-halves. That's a certainty.
"We have to keep our eyes on what's available to us. (But) it's tough because some of the ones we want aren't going to be allowed out on loan, so if we can't get them in on a permanent in this next week or so then the deal won't go through."
Source: PA
