Trades, including gunmaking, tended to run in families. So, there is likely a family connection between the Garrets. Also, note that as a Birmingham shop, Garret could have supplied anything a customer was willing to pay for. What he couldn't do in his shop he could easliy get from other shops or from out-workers (some very highly specialized.) Any style of quality grade can come from any shop. It was all about satisfying the customer if said customer was willing to pay the price.