You can get much better than that. Ignore people who say that you can't get good accuracy out of a .22lr, they simply do not know what they are talking about.
First, get rid of the Tasco, Tasco is another word for Junk. If money is an issue, the best scope for under $150 is the Center Point 4-16x40 (79.98 @Walmart). If you wish to sink more money into a scope, feel free, but there is definitely a point of diminishing returns with .22 scopes. The Center Point will do you justice. Works very nicely on .17's & .22WMR's as well.
Second, even if everything fit back together properly...you need to glass bed the rifle. The purpose of bedding the action is to get a better fit than possible with a wood chisel. The goal is to bed the action in such a way that there is no stress or twisting when the screws are tightened.
If you have a gunsmith bed it for you, it averages around $40-80. Different gunsmiths may bed a little different from one to another but most think that the recoil lug should be bedded, the area directly under the screws front and back should be bedded and the middle part where the cartridges feed through should have clearance. Also the first couple of inches of the barrel under the chamber many people feel should be bedded to take some of the hanging weight off the receiver...or you can free-float it...your choice, tell 'em what you want.
Third, purchase a micrometer caliper, (I prefer the ones with Vernier Scale, measures to .0001 of an inch, but you really only need to go to .001 with .22's, I'm just a little OCD

). With the Marlin Micro-groove barrel, bullet diameter is KEY. Most people don't know that you need a fatter bullet for the micro-grooves to really GRAB and twist...but once you find the proper round...your accuracy becomes Better Than Average. If you are firing improperly sized bullets in your rifle, you will have rounds flying off in odd directions instead of grouping properly in a cloverleaf. Buy several different boxes of ammo, measure a sampling (10-20) of each box, and Write it down. Then fire approx 50-100 shots (or the whole box) and record the groups. You will find the proper ammo for your Marlin or any other pistol/rifle with this method. Even Bulk ammo has consistancy, find out which bulk ammo works best. Mine prefers CCI...
Fourth, consider a bipod, Rock Creek makes one that can be found for $40 at almost any walmart/gunstore. I've only found one benchrest that didn't move, and it was bloody expensive, not to mention rather large & heavy

A bipod stabilizes the front on top of the shooting bench/ground/etc and allows you to focus on one plane of movement.
Fifth, intentionally use a
slight up/down motion when bringing to bear on target, I let my breathing move the butt of the rifle up/down like an archer uses the up/down to target with before release. This focuses your movements into the up/down instead of allowing side-side movement (which is for skeet & running/flying game). For target shooting, nothing is moving except you, so use the up/down to your advantage, which leaves only figuring out Windage as you go and the wind blows
These should get you within 1" inch groups at 50 yards with ease. 1/2" if you are as anally retentative as the rest of us Black Death shooters.